Method for the preparation of aminoethylethanolamine



United States Patent M 3,383,417 METHOD FUR THE PREPARATION 0F AMINOETHYLETHANOLAMENE Myrl Lichtenwalter, Austin, Tex., assignor to Jefferson Chemical Company, Inc, Houston, Tex, a corporation of Delaware No Drawing. Filed Dec. 21, 1964, Ser. No. 420,119

2 flairns. (Cl. 260584) ABSTRACT OF THE DISCLOSURE Aminoethylethanolamine is obtained in preponderant yield by contacting monoethanolarnine in the absence of added ammonia with a catalyst containing a major amount of nickel, copper and a minor amount of chromium oxide, manganese oxide, molybdenum oxide and/ or thorium oxide at a temperature of 150 to 250 C. and a pressure of 2,000 to 4,000 p.s.i.g. correlated so as to provide for the total conversion of about to 30% of the monoethanolamine.

This invention relates to a method for the production of a dimerized amine feed stock. More particularly, this invention relates to a method for dimerizing monoethanolamine in order to provide a high yield of 2-(2-a1ninoethylamin0)-ethanol, hereinafter referred to as aminoethylethanolamine.

Aminoethylethanolamine is useful for a variety of purposes, such as those related to the general areas of textile treating and sequestering. In particular, aminoethylethanolamine has been used as an intermediate in the preparation of cationic textile softening agents, sequestering agents, etc. As shown, for example, by Wilkes U.S. Patent No. 2,479,657, it can also be used as a raw material for the preparation of pipenazine.

Theoretically, aminoethylethanolamine could be prepared with comparative ease by reacting monoethanolamine with itself in accordance with .the following equation:

HgNCHzCHzOH H NCH CHzOH However, as shown by the Wilkes patent and other references, aminoethylethanolamine can also be converted to piperazine by the elmination of water as shown in the following equation:

Normally, the conversion of aminoethylethanolamine to piperazine is accomplished in the presence of a hydrogenation catalyst. It is also known to prepare piperazine from monoethanolamine as shown, for example, by Moss et al. U.S. Patent No. 3,151,115 and Moss et al. U.S. Patent No. 3,037,023. Both of these conversions are normally accomplished in the presence of a hydrogenation catalyst such as a nickel, cobalt or copper hydrogenation catalyst. As a consequence, although it is known that aminoethylethanolamine is present in a 'by-product form when monoethanolamine is converted to piperazine, the reaction of monoethano-lamine with itself over a hydrogenation catalyst has been considered a poor approach to 3,383,417 Patented May 14, 1968 significant production of aminoe'thylethanolamine because of the propensity of the product to cyclize.

It has now been surprisingly discovered, however, that monoethanolamine can be reacted with itself in the presence of a selected class of hydrogenation catalysts under reaction conditions, as hereinafter defined more fully, to provide the aliphatic dimer, aminoethylethanolamine, rather than the heterocyclic dimer, piperazine.

In general, this is accomplished when monoethanolamine is reacted with itself in the optional presence of water, but in the absence of added ammonia and in the presence of a hydrogenation catalyst, as hereafter defined, under reaction conditions including a pressure of about 2,000 to about 4,000 p.s.i.g. (composed of at least of hydrogen partial pressure) at a temperature within the range of about to about 250 C.; such reaction conditions being correlated to provide for an overall conversion of monoethanolamine to amine products of about 10% to about 30%. More preferably, the pressure will be composed in part primarily by hydrogen and will be within the range of about 2,500 to about 3,000 p.s.i.g., the temperature will be within the range of about to about 200 C. and the conversion will be within the range of from about 20% to about 30%.

The foregoing reaction conditions may be appropriately correlated with space velocity in obtaining the desired conversion. Thus, the space velocity may suitably be within the range from about 0.4 to about 3 grams of monoethanolamine per hour per milliliter of catalyst.

The catalyst to be employed in accordance with the present invention will contain, as the active ingredient, nickel, copper and chromium oxides containing, on an oxide-free basis, from about 60 to about 85 mol percent nickel, from about 14 to about 37 mol percent copper and from about 1 to about 5 mol percent of chromium. Still more preferably, the catalyst will contain, on an oxide-free basis, 72 to 78 mol percent nickel, 20 to 25 mol percent copper and 1 to 3 mol percent chromium. A specific example of a preferred catalyst is one containing about 75% nickel oxide, about 22% copper oxide and about 3% chromium oxide. This mixture of oxides, when reduced with hydrogen at a temperature of less than about 400 C., will provide a final composition wherein the nickel and the copper oxides are reduced to metallic nickel and metallic copper but wherein the chromium oxide remains present as chromium.

Thus, chromium oxide, may be considered as a nonreducible metal oxide for the catalyst in question. It may be replaced with other non-reducible metal oxides such as manganese oxide, molybdenum oxide, thorium oxide, etc.

The invention will be further illustrated in respect to the following examples which are given by way of illustration and not as limitations on the scope of this in vention.

EXAMPLE I A series of seven one-hour runs were made by feeding monoethanolamine or a mixture of monoethanolamine and water at 3,000 psi. hydrogen pressure through a reactor filled with a nickel-copper-chromia catalyst containing about 75 nickel, about 22% copper and about 2% chromium. Samples of the reactor efiiuent were analyzed, and the yields were determined from the analysis.

The reaction conditions employed and the results ob tained are set forth in the following table.

TAB LE 1 Feed Comp, wt. Yield, mol percent acyclic Cyclic Run No. wt. percent Space vel., Temp, MEA

g.ll1r.lm1. C. Conv. AEEA 2 DETA 3 EDA 4 Total Pip. AEI HEP 7 Total MEA 1 H 1 MEA=monoethanolamine. 5 Pip.=piperazine. 1 AE EA aminoethylethanolamin0. AE P =N-arninoethylpiperazine. 3 DETA-diethylenetriamine. 7 HEP=N-hydroxyethylpiperazine.

4 EDA =etl1y10nediamine.

As can be seen from the foregoing table, only a minor 15 0.5 to 3 grams of monoethanolamine per milliliter of amount of aminoethylethanolamine was obtained With catalyst per hour in the presence of hydrogen, said new conversion about 40%, the best results being obtained tion conditions being correlated to provide a conversion at conversions of 30%, or less, and still more preferably, of monoethanolamine of from about 1.0% to about 30%, at conversions within the range of 10% to 25%. whereby the predominant reaction product is amino- 20 ethylethanolamine, said catalyst containing, as the ac- V EAAMPLE H tive ingredient, nickel, copper and a non-reducible metal A series of runs were made by passing mon ct oloxide in the proportions, on an oxide-free basis, of about amim at 0 13.8.1. hydrogen pressure through a reacto about mol percent nickel, 14 to 37 mol per tor containing a hydrogenation catalyst that differed cent copper and 1 to 5 mol percent of the non-reducible from the catalyst in Example I only through the replace- 25 metal oxide, said non-reducible metal oxide being selected ment of nickel with cobalt. Thus, the catalyst contained from class consisting of chromium oxide, manganese about 75% cobalt, about 22% copper and about 3% oxide, molybdenum oxide and thorium oxide. of chromium. 2. A method as in claim 1 wherein the pressure is The reaction cond1t1ons employed and the results obwithin the range of 2,500 to 3,000 p.s.i.g., the temperatained are set forth in Table 2. ture is within the range of 175 to 200 C., wherein the TABLE 2 Feed C0n1p., Yield, mol ercent ac elic Run No. wt. percent Spafio lvcli, T511011)" (ltj IEA AEEA p y Cyclic g. r. 111. onv. 2 DE'IA3 EDA T t 7 MEA H20 0 a1 Pip AEP HEP Total 33.3 2 12 150 23 47.4 0 a 10.7 59.0 2 33.3 0 45 135 24 24.1 3.4 32.5 22.1 5 1.2 i 49? 20 1 13 152 25 47.8 1.7 6.1 55.6 31.0 3.1 5.2 44.3 1 07 153 26 45.6 1.1 3.1 54.8 28.8 3.9 7.5 45.5 0.94 150 33 29.6 7.3 34.4 41.2 11.0 0.5 62.6 33.3 1 10s 38 25.7 1.0 7.6 34.3 43.8 12.6 9.3 53.7 33.3 1 15 53 12.5 0.9 5.3 10.0 51.5 13.4 10.2 81.1

1 MEA =monoethanolan1ine. 5 Pip.=piperazine. 2 AEEA=aminoethylethanolainino. 6 AEP=N-aminoethylpiperaziuo. 3 DETA=diethylcnetriamine. 7 HEP=N-hydroxyothylpiperazino. 4 EDA=cthylenediamina As will be seen from the results of this experiment, conversion is within the range of about 10% to about cobalt-copper-chromia catalysts exh1b1ted a far greater 25% and wherein the catalyst contains, on an oxide-free tendency towards ring closure than the nickel catalyst, basis, from about 72 to 78 mol percent nickel, 20 to 25 as is illustrated by the sum of yield of heterocyclic com- 50 mol percent copper and 1 to 3 mol percent chromium, pounds (piperazine, hydroxyethylpiperazine and aminoethylpiperazine). References Cited What is claimed is: UNIT 1. A method for the preparation of aminoethylethanol- 3 O37 023 5/ 5 i :JATENTS 260 268 amine hich c rises cont ctin monoeth 01 min 055 e a W omp a g a e m 55 3,151,115 9/1964 Moss et al. 260-268 the absence of added ammonia with a hydrogenation catalyst under conversion conditions within the general CHARLES E PARKER range of 2,000 to 4,000 p.s.i.g., a temperature of Primary Examme" C. to 250 C. and a space velocity within the range of PHILLIPS, Assistant x 

